This invention relates to electronic appliances, for example, cassette tape decks, and is more particularly directed to electronic equipment components in which various modes of operation can be set by entering setting information on push buttons, touch switches, or other switches on an operating panel, after which the setting information is stored in a memory lock or latch and controls particular functional elements of the electronic equipment component. For example, in a cassette tape deck, such setting information can be entered and stored to control recording level, recording balance, and playback or output level.
Recently, improvements in performance and reductions in cost have been made possible by the use of digital integrated circuitry in domestic appliances, especially audio equipment. Marked advances made in recent years in digital and computer technology have permitted such digital circuitry to be used extensively to replace many expensive, cumbersome, and often unreliable mechanical and electromechanical components in these domestic appliances.
However, application of digital technology to a domestic appliance also gives rise to complexity of operation, which can lead to operator error. This problem is especially prevalent where the appliance is an article of taste, such as a cassette tape deck, and where the appliance has many diverse functions to be controlled by digital circuitry.
For example, in a digitally controlled cassette tape deck, various parameters such as recording level, output level, recording balance, tape type selection (i.e., normal, high-bias, chrome-oxide, etc.), and noise-reduction selection can be selected on touch switches or other like devices. This information is transmitted to a latch or memory lock, where it is used to control the elements associated with each of the above parameters. Preset setting information can also be stored in a digital memory to set each of the parameters to any of one or more preset arrangements, which can be changed to a preference state by use of the touch switches.
A display is associated with each of these parameters, i.e., recording level, output level, recording balance, tape type selection, and noise-reduction selection, and shows the contents of the memory lock or latch, that is, the values of the parameters actually in use.
With such an arrangement if a change is to be made in the preset state, the stored information in the memory has to be provided to the latch, so that the information can be displayed. Then the information is changed by means of the associated touch switches. If the actual setting for one of the parameters is changed when the preset information is read out from the memory, it often occurs that a consumer operator will erroneously change the preset information at the time that the operating parameter is changed to a preference level.
It is also confusing for a consumer to operate this type of appliance in that there is no simple means to check the information stored in the memory without disturbing the information stored in the latch. Further, there is no indication provided on the operating panel if any of the information furnished from the memory to the latch has been altered.